The invention relates to the field of fastening plates for use with fasteners to secure membranes to substrates and, in particular, a fastening plate for securing a membrane to a substrate forming a foundation wall of a structure.
Fastening plates are known which, when used with a fastener, secure a membrane to a substrate. For example, known fastening plates are used to fasten roofing sheets to a roof, as disclosed in U.S. Pat. No. 5,951,225 (Osterle et al.). Among other things, a fastening plate for use with roofing sheets is typically intended to provide a waterproof seal where the fastening plate meets the membrane.
A high density polyethylene membrane for use with building foundations is known. The membrane is designed to minimize the amount of water which enters a building through that part of the foundation which is below the surface of the surrounding soil. The membrane has a dimpled portion which includes an array of dimples, and a top portion which is substantially smooth. Because it is dimpled, the membrane holds soil and moisture in the soil away from the foundation wall, and provides an air gap between the membrane and the foundation wall exterior. Typically, the membrane is secured to the foundation wall exterior along a top portion of the membrane, so that the membrane hangs like a curtain over the foundation wall.
After the membrane is secured to the foundation wall, soil is backfilled against the membrane. A foundation drainage tile is typically installed at the foundation footings. Any moisture which does get past the membrane moves through the air gap to the foundation drainage tile, and is drained away through the tile.
It is important that the top portion of the membrane be well secured to the foundation wall so that soil will not fill the air gap and clog the drainage path. The top portion of the membrane typically is fastened by a plurality of fasteners installed with a plurality of washers in the top portion, as is known in the art, and a plurality of additional fasteners and washers, in the dimpled portion of the membrane. Depending on the circumstances, a relatively large number of fasteners and washers may be needed.
There is a continuing need for an improved fastening plate for securing a membrane having a dimpled portion and a smooth top portion to a substrate.
In a broad aspect of the present invention, there is provided a fastening plate for securing a membrane to a substrate. The membrane has an inner side to be positioned adjacent to the substrate and an outer side disposed opposite to the inner side, and a dimpled portion including an array of dimples and a substantially smooth portion. The dimples form depressions on the outer side of the membrane and corresponding projections from the inner side. The fastening plate has a mating portion including a contact side to be positioned adjacent to the outer side of the membrane and an exposed side disposed opposite to the contact side, and a biasing portion extending from the mating portion, for urging the smooth portion of the membrane against the substrate. The mating portion includes an array of locator elements projecting inwardly from the contact side and adapted to cooperate with a corresponding number of the dimples to position the mating portion on the dimpled portion. The mating portion is adapted to receive at least one fastener for securing the fastening plate to the substrate.
In another aspect there is provided an improvement in a sheathing assembly for securing a membrane to a substrate. The sheathing assembly includes the membrane, a fastening plate and at least one fastener, the fastening plate having at least one aperture for receiving the fastener. The membrane has a dimpled portion including an array of dimples, and a smooth portion which is substantially planar. The membrane also has an inner side to be positioned adjacent to the substrate and an outer side disposed opposite the inner side. The dimples form depressions on the outer side of the membrane and corresponding projections from the inner side. The fastening plate has a contact side to be positioned adjacent to the outer side of the membrane and an exposed side disposed opposite the contact side. The sheathing assembly also includes the improvement in which the fastening plate has an array of locator elements projecting inwardly from the contact side and adapted to cooperate with a corresponding number of dimples formed on the outer side of the membrane to position the fastening plate on the dimpled portion.
In yet another aspect, there is provided a method of securing a membrane to a substrate by a fastening plate and at least one fastener, the membrane having a dimpled portion including an array of dimples and a smooth portion which is substantially planar. The membrane has an inner side to be positioned adjacent to the substrate and an outer side disposed opposite the inner side, the dimples forming depressions on the outer side and corresponding projections from the inner side. The fastening plate has a contact side to be positioned adjacent to the outer side of the membrane, and an exposed side disposed opposite the contact side. The fastening plate also has a mating portion including an array of locator elements projecting inwardly from the contact side and adapted to cooperate with a corresponding number of dimples and at least one aperture for receiving the at least one fastener, and a biasing portion, the biasing portion extending from the mating portion. The method includes placing the inner side of the membrane adjacent to the substrate, placing the contact side of the fastening plate adjacent to the outer side of the membrane, positioning the fastening plate relative to the dimpled portion and the smooth portion by cooperation of the locator elements with a corresponding number of dimples, so that the mating portion is disposed on the dimpled portion and the biasing portion is disposed on the smooth portion, and inserting the at least one fastener through the at least one aperture to secure the fastening plate to the substrate, so that the biasing portion urges the smooth portion against the substrate.
In yet another aspect, there is provided a fastening plate for securing a membrane to a substrate. The membrane has an inner side to be positioned adjacent to the substrate and an outer side disposed opposite to the inner side, and a dimpled portion including an array of dimples and a substantially smooth top portion. The dimples form depressions on the outer side of the membrane and corresponding projections from the inner side. The fastening plate has a mating portion including a contact side to be positioned adjacent to the outer side of the membrane and an exposed disposed opposite to the contact side. The mating portion includes at least one aperture for receiving at least one fastener. The mating portion includes an array of locator elements projecting inwardly from the contact side and adapted to cooperate with a corresponding number of the dimples to position the mating portion on the dimpled portion so that the aperture is positioned between the dimples.